The Sinkhole Trail is a network of Limestone Coast sinkholes that surround The Bellum Hotel, a popular hotel pub between Mt. Gambier and Port MacDonnell, SA. Whether you are a diver, love to snorkel, want to jump in on hot days or just enjoy experiencing all the interesting and beautiful nature of the sinkholes...they are all worth taking the trail to see!

Little Blue Lake is a water-filled doline in the Australian state of South Australia located in the state's south-east in the locality of Mount Schank about 20 kilometres (12 mi) south of the municipal seat of Mount Gambier. It is notable locally as a swimming hole and nationally as a cave diving site. It is managed by the District Council of Grant and has been developed as a recreational and tourism venue.

More than just a watering hole

Located in the middle of a sheep farm located 10 minutes from Mount Gambier, Kilsby Sinkhole is an amazing natural wonder with a unique and fascinating history. Once little more than a watering hole for traveling stockmen who would throw a bucket into water below and haul it to ground level to quench the thirst of their cattle, the sinkhole has since been central to 4 generations of farming activity by the Kilsby Family.

A divers’ delight

Drawing divers because of the shimmering crystal-clear water of the chamber below, the site was one of the first sinkholes to be dived in the Mount Gambier region, with recreational diving activity commencing in the late 1950s. The site attracted a large number of people who flocked to the site on news of its natural beauty and renowned water clarity.

Fossil Cave (5L81), formerly known as The Green Waterhole, is a cave in the Limestone Coast region of south-eastern South Australia. It is located in the gazetted locality of Tantanoola^[1] about 22 kilometres (14 miles) north-west of the city of Mount Gambier, only a few metres from the Princes Highway (Route B1) between Mount Gambier and Millicent. It is notable both as a paleontological site and as a cave diving site.

The beauty of the Umpherston Sinkhole has to be seen to be believed. Appreciate its size and depth from the viewing platforms at the top of the sinkhole, then walk down into the sinkhole, along the terraces and behind the hanging vines. The resident colony of possums make an appearance at dusk and enjoy being fed fresh fruit (no bread please).

A large undercover shelter with group seating and free barbecue is provided. The kiosk on site offers coffee, snacks, ice creams and souvenirs. Umpherston Sinkhole, also known, as the sunken garden was once a cave formed through dissolution of the limestone. The sinkhole was created when the top of the chamber collapsed downwards.

Hell’s Hole is one of the most impressive karst features in the Limestone Coast.

It is a cenote – a sinkhole that extends into open water – and is approximately 45m in diameter, 25m deep and 38m below the viewing platform.

A walking trail has been established at the site, which meanders uphill to the sinkhole with an easy walk to the carpark.

Take a deep breath before you step onto the viewing platform – the view in to Hell’s Hole is like nothing you have experienced before!

While anyone can visit and take in the view from the platform, Hell’s Hole is also popular among divers. To dive at Hell’s hole, divers must obtain a ForestrySA permit and be a member of either the Cave Diving Association of Australia (CDAA) or Australian Cave Explorers (ACE).

Piccaninnie Ponds Conservation Park, formerly the Piccaninnie Ponds National Park, is a protected area of 862 hectares (2,130 acres) located in southeastern South Australia near Mount Gambier.

Ewens Ponds is a series of three water-filled limestone sinkholes in the Australian state of South Australia located in the gazetted locality of Eight Mile Creek on the watercourse known as Eight Mile Creek about 25 kilometres (16 miles) south of Mount Gambier and 8.4 kilometres (5.2 miles) east of Port Macdonnell.^[2] The ponds are popular with recreational divers due to underwater visibility of up to 80 metres (260 feet).^{[verification needed]} It has a large fish population including the endangered golden pygmy perch. Ewens Ponds has been part of the Ewens Ponds Conservation Park since 1976.

Ask anyone about a dive site that comes easily to mind and you can bet that it has some sort of feature that is unique amongst others. Whether it’s the aquatic life you’re likely to see, dramatic topography or stunningly clear water, something is likely to set it apart. For this entry I want to discuss a well known site in Mount Gambier. Ask divers about it and you can bet that one of the first things they are likely to mention is where it’s located. Allendale Cave is not located in a forest or the side of a hill or a coastline or even in someone’s paddock. No, it’s located slap bang in the middle of a road!

The main features of the sinkhole include fish and yabbies, as well as thermoclines in 15-meter deep water. It is 26 metres deep and 26 metres wide.

Water visibility is known to be generally good; it’s frequently used by divers and students alike for training purposes.

To dive here, interested individuals are required to obtain permission from the Department of Environment and Water. All bookings should be sent in via email at least two business days before the date. Applications should include the names of all divers, relevant booking dates, CDAA numbers, and a contact number.

The roadside provides easy access to Gouldens Waterhole, and it’s equipped with a diver’s change table.